The surface molecule CCR5 is found on tumor cells within liver metastases of colorectal cancer. Inhibition of this molecule leads to a reduction in growth signals for tumor cells and subsequent slowed or halted tumor growth. The agent for the inhibition of CCR5 has already received FDA approval for treatment of HIV and has shown little side effects and toxicities even on long term treatment. Therefore CCR5-inhibition has the potential of providing non-toxic tumor growth inhibition.